Chapter 6, Problem 44P

(a)

Interpretation Introduction

Interpretation: The mechanism by curved-arrow notation for below reaction should be written.

  

Concept introduction:Bimolecular substitution or ${\text{S}}_{\text{N}}2$ proceeds via single -step mechanism. Thus it is well known as concerted mechanism. Nucleophile approaches carbon while the leaving group still departs from the rear side (opposite to leaving group). The transition state only illustrates the geometric orientation of the substrates and reagents as they pass through the maxima in the single-step mechanism.

A general ${\text{S}}_{\text{N}}2$ reaction mechanistic pathway is illustrated as follows:

  

${\text{S}}_{\text{N}}2$ pathway as it is a stereospecific reaction. This essentially means the R stereoisomer can only lead to inverted S stereoisomer and vice versa. Thus the outcome is the rear side displacement of leaving group.

(b)

Interpretation Introduction

Interpretation:The mechanism by curved-arrow notation for below reaction should be written.

Concept introduction:Bimolecular substitution or ${\text{S}}_{\text{N}}2$ proceeds via single -step mechanism. Thus it is well known as concerted mechanism. Nucleophile approaches carbon while the leaving group still departs from the rear side (opposite to leaving group). The transition state only illustrates the geometric orientation of the substrates and reagents as they pass through the maxima in the single-step mechanism.

A general ${\text{S}}_{\text{N}}2$ reaction mechanistic pathway is illustrated as follows:

  

${\text{S}}_{\text{N}}2$ pathway as it is a stereospecific reaction. This essentially means the R stereoisomer can only lead to inverted S stereoisomer and vice versa. Thus the outcome is the rear side displacement of leaving group.

(c)

Interpretation Introduction

Interpretation:The mechanism by curved-arrow notation for below reaction should be written.

  

Concept introduction:Bimolecular substitution or ${\text{S}}_{\text{N}}2$ proceeds via single-step mechanism. Thus it is well known as concerted mechanism. Nucleophile approaches carbon while the leaving group still departs from the rear side (opposite to leaving group). The transition state only illustrates the geometric orientation of the substrates and reagents as they pass through the maxima in the single-step mechanism.

A general ${\text{S}}_{\text{N}}2$ reaction mechanistic pathway is illustrated as follows:

  

${\text{S}}_{\text{N}}2$ pathway as it is a stereospecific reaction. This essentially means the R stereoisomer can only lead to inverted S stereoisomer and vice versa. Thus the outcome is the rear side displacement of leaving group.

(d)

Interpretation Introduction

Interpretation:The mechanism by curved-arrow notation for below reaction should be written.

  

Concept introduction:Bimolecular substitution or ${\text{S}}_{\text{N}}2$ proceeds via single -step mechanism. Thus it is well known as concerted mechanism. Nucleophile approaches carbon while the leaving group still departs from the rear side (opposite to leaving group). The transition state only illustrates the geometric orientation of the substrates and reagents as they pass through the maxima in the single-step mechanism.

A general ${\text{S}}_{\text{N}}2$ reaction mechanistic pathway is illustrated below:

  

${\text{S}}_{\text{N}}2$ pathway as it is a stereospecific reaction. This essentially means the R stereoisomer can only lead to inverted S stereoisomer and vice versa. Thus the outcome is the rear side displacement of leaving group.